The invention relates to a method for producing a three-dimensional fiber composite component using fiber bundles.
Various production variants for fiber-reinforced plastic components are known from the prior art, inter alia a CFRP shell design, CFRP woven design, or CSMC design. Furthermore, production methods with hollow profiles or the use of sheet metal shells have been known for a long time. Despite continuous development and adaptation even to mass production, the components which are produced in the process are comparatively expensive and/or heavy.
German patent application DE 10 2013 219 820 A1 describes a method for producing a fiber composite component using fiber bundles, as a result of which weight and costs can be saved. It is provided here, for connecting fiber bundles with a matrix made from thermoplastic and/or thermosetting material, that they form a profile and bracing means are arranged between the fiber bundles.
In the known method, fiber bundles have to be reshaped in different directions and with different curvatures, in order to ensure the predetermined component shape.
It is an object of the present invention to provide a method, by way of which the fiber bundles can be reshaped easily, inexpensively, and with as little use of tools as possible. Furthermore, a reshaping device is to be provided, by way of which fiber bundles can be reshaped three-dimensionally more rapidly and without an additional use of tools.
These and other objects are achieved by way of a method and an apparatus in accordance with embodiments of the invention.
Here, according to the invention, a method for producing a three-dimensional fiber composite component with fiber bundles is provided in principle, the fiber bundles being reshaped from a rod-shaped or strand-shaped initial form into a three-dimensional predetermined component shape via a shape defining apparatus. The shape defining apparatus comprises at least one reshaping channel which has a first curvature which is predetermined for the fiber composite component along its longitudinal direction and configures at least one leading edge. The fiber bundles are pressed against the at least one leading edge of the reshaping channel and, in the process, adopt the predetermined first curvature. The predetermined first curvature corresponds to a curvature along the longitudinal extent of the fiber bundle. The leading edge is formed by way of a lateral outer wall of the reshaping channel.
In addition, the method according to the invention is distinguished by a reshaping operation in a further direction which is substantially perpendicular with respect to the first direction. For this purpose, a shaping edge is configured along the reshaping channel on the bottom side, against which shaping edge the fiber bundles are pressed and, in the process, adopt a predetermined second curvature for the fiber composite component. The first and second curvature are brought about, for example, in the X- and Z-direction in the reshaping channel, the fiber bundles extending in the Y-direction and all directions lying perpendicularly with respect to one another. The method steps are then formed by a fiber bundle first of all being fed to a reshaping channel of the shape defining apparatus, subsequently being pressed against the leading edge of the reshaping channel, and finally being pressed against the bottom-side shaping edge. The result is that a three-dimensional final shape of the respective fiber bundle is set. The movement directions are preferably in each case perpendicular with respect to one another, that is to say the feeding of the fiber bundle takes place in the Z-direction, the pressing onto the leading edge takes place in the X-direction and the pressing onto the shaping edge again takes place in the Z-direction.
It is favorable here that tool devices such as slides and the like are not additionally required, as a result of which the production costs can be reduced.
In one exemplary embodiment, the leading edge forms a step with respect to a feed section, with the result that the fiber bundle can be introduced into the reshaping channel and can subsequently be pressed against the leading edge.
In one favorable embodiment, the fiber bundles are impregnated with resin or are resin-impregnated thermoplastic fiber bundles. Furthermore, the fiber bundles are preferably formed from endless fibers and with glass fibers or carbon fibers. The fiber bundles can be configured with a round, rectangular or square cross section and, in the latter case, have a size of approximately 10×10 mm.
Final finishing of the fiber composite component with the three-dimensionally reshaped fiber bundles which have the first and second curvature takes place in a conventional press tool.
The invention also includes the simultaneous reshaping of a plurality of fiber bundles, the shape defining apparatus having a plurality of reshaping channels for this purpose. Here, the reshaping channels can extend substantially in parallel along the X-direction of the shape defining apparatus. The fiber bundles can be held via a tensioning frame and can be fed to the individual reshaping channels. It is advantageous here that a multiplicity of fiber bundles can be set into the final shape more rapidly and a plurality of components can be reshaped in one tool.
Furthermore, it is provided in one embodiment of the invention that the plurality of reshaping channels of the shape defining apparatus have different first curvatures and/or leading edges with different second curvatures, with the result that a plurality of fiber bundles are reshaped at the same time into different three-dimensional shapes for the three-dimensional fiber composite component. The different structures make any desired shape of the fiber composite component in 3D possible.
Furthermore, the invention includes the shape defining apparatus for rod-shaped or strand-shaped fiber bundles for three-dimensional reshaping of the fiber bundles and an above-described embodiment. The shape defining apparatus is advantageously distinguished by the fact that fiber bundles can be reshaped three-dimensionally in at least one or two directions without additional tools.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.
The figures are diagrammatic by way of example. Identical designations denote identical parts in all views.